Method of casting stereotype plates



Dec. 26, 1933. Q wlNKLER METHOD OF CASTING STEREOTYPE PLATES Filed March20, 1951 5 Sheets-Sheet l Des. .26, 1933- c. WINKLER METHOD OF CASTINGSTEREOTYPE PLATES Filed March 20. 1931 5 Sheets-She'et 2 Dec. 26, 1933.c. WINKLER 1,940,737

METHOD OF CASTING STEREOTYPE PLATES Filed March 20. 1961 5 Sheets-Sheet3 T e J fiwcnzor: C22 hikfi/er .2 W

Dec. 26, 1933. c. WINKLER 1,940,737

METHOD OF CASTING STEREOTYF'E PLATES Filed March 20, 1931 5 Sheets-Sheet4 Dec. 26, 1933. c. WINKLER METHOD OF CASTING STEREOTYPE PLATES FiledMarch 20, 1931 5 Sheets-Sheet 5 Patented Dec. 26, 1933 UNITED STATESPATENT OFFICE METHOD OF CASTING STEREOTYPE PLATES Application March 20,1931, Serial No. 523,978, and in Germany April 19, 1930 1 Claim.

In casting stereotype plates and backing electros under the pressure ofthe metal in the melting pot, which is controlled by a valve, or otherorgan, such as is described, for example, in my Patent 1,244,935, it isfound that a bur is formed along the edges of the casting, when theparts of the mold are worn and therefore do not fit together quitetightly.

The object of the present invention is to avoid the formation of thisbur or ragged edge.

In order to accomplish this, I provide means whereby the metal whichflows into the mold during the casting process is not subjected to thefull static pressure generated by the metal in the melting pot proper.The result of this is that due to the decreased pressure under which themold is being filled, the stresses within the mold are reduced to aPlates cast by this method are quite free from all bur along the edges,and the matrices are subjected to less stresses, so that they are not soeasily torn or picked.

After the mold has been filled with metal, the contents of the mold,while solidifying, are pref erably subjected to the full static pressureof the metal in the pot, in order to prevent hollow spaces from beingformed in the casting.

According to the preferred form of my invention, I provide either anauxiliary chamber or a bye-pass which may be in constant communicationwith the melting pot proper, or brought intocommunication therewith bymeans of a valve. This chamber or bye-pass is so arranged that the metalwhich is to fill the mold will flow from the melting pot through thechamber or bye-pass, and thence-into the mold at a lesser dynamicpressure than would be the case if the metal were to flow direct fromthe melting pot into the mold.

In the accompanying drawings various-ways of carrying out my inventionare shown by way of example, in connection with a melting pot providedwith a rotary valve or cock for regulating the flow of metal from thepot into the mold.

Fig. 1 is a diagrammatic section of a pot and mold showing'the valve inclosed position,

'Fig. 2 is a section through the same parts in the position in which themold is being filled,

Figs. 3 and 4 represent another form of pot with the valve in twopositions which correspond with Figs. 1 and 2,

Figs. 5, 6 and 7 show another construction of the valve, in threedifferent positions,

Figs. 8 and 9 are sections of another construction of pot with the valvein the closed position in Fig. 8, and in the open position in Fig. 9,

Figs. 10, Hand 12 show a further construction with the valve in threedifferent positions.

The melting pot a (Figs. 1 and 2) against which the mold b is pressedfor casting, has a chamber 0, at the bottom, which in the closedcontents of the pot. 'venient form, for example holes 6, can beproposition of the valve d communicates with the An air-escape in anyconvided, in order to enable the metal to flow in. and out of thechamber 0 sufliciently quickly.

When the valve d is turned into the position shown in Fig. 2, the metalflows out of the chamber c into the mold b, without the pressure of themetal in the pot entering into action. Consequently the dynamicpressure, which arises while the form is being filled, is much less thanwhen the metal fills the mold under the full head of the metal in thepot.

The chamber 0 can also extend somewhat upwards, in order to increase thehead pressure somewhat, as shown in Figs. 3 and 4. The width of thechamber c can be chosen according to circumstances.

The construction shown in Figs. 5 to 7 differs from that shown in Figs.1 to 4 by the fact that the valve d which, in the closed position (Fig.5) connects the contents of the metal pot with the chamber 0, and, inthe open position (Fig. 6), enables the mold to be filled under thereduced head of the metal in the chamber 0, can also be turned into athird position (Fig. 7) which allows the full head of the metal in thepot to act on the metal in the mold while it is solidifying.

In the further construction shown in Figs. 8 and 9 a part of the metalpot is divided off by a wall forming a chamber 0 over the valve d, whichchamber, by opening the valve (Fig. 9), can be brought intocommunication with the mold b. This chamber is emptied into the mold, assoon as the valve is opened, but metal flows from the pot through theholes e in the top wall of the chamber 0 and fills this chamber again,so that then the full head of metal in the pot will act on the platewhile it is solidifying in the mold.

My invention can also be carried out with a metal pot having no chamberdivided ofi, but having a valve d (Figs. 10 to 12) which is first onlypartially opened through a bye-pass of small section (Fig. 11) so thatthe metal is throttled in filling the mold, and does not thereforeproduce so much dynamic pressure. When the mold is full, the valve d isopened entirely (Fig. 12) so that the metal in the mold will solidifyunder the full pressure of the metal in the pot.

What I claim and desire to secure by Letters Patent of the United Statesis:

The method of casting stereotyp plates consisting in bye-passing aportion of the metal in a melting pot, filling a mold with metal whichpasses through said bye-pass and at a lower static pressure than that ofthe metal in said melting pot, and then putting the full static pressureof the metal in the pot on the metal in the mold while the latter issolidifying in the mold.

' CARL WINKLER.

